title: Optimization of coagulation-flocculation treatment on paper-recycling wastewater: Application of response surface methodology.
abstract: The application of coagulation-flocculation (CF) process for treating the paper-recycling wastewater in jar-test experiment was employed. The purpose of the study was aimed to examine the efficiency of alum and poly aluminum chloride (PACl) in combination with a cationic polyacrylamide (C-PAM) in removal of chemical oxygen demand (COD) and turbidity from paper-recycling wastewater. Optimization of CF process were performed by varying independent parameters (coagulants dosage, flocculants dosage, initial COD and pH) using a central composite design (CCD) under response surface methodology (RSM). Maximum set required 4.5 as pH, 40 mg/L coagulants dosage and 4.5 mg/L flocculants dosage at which gave 92% reduction of turbidity, 97% of COD removal and SVI 80 mL/g. The best coagulant and flocculants were alum and chemfloc 3876 at dose of 41 and 7.52 mg/L, respectively, correspondingly at pH of 6.85. These conditions gave 91.30% COD and 95.82% turbidity removals and 12 mL/g SVI.
authors.affiliation: Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran.
authors.forename: Noushin
authors.initials: N
authors.lastname: Birjandi
authors.forename: Habibollah
authors.initials: H
authors.lastname: Younesi
authors.forename: Nader
authors.initials: N
authors.lastname: Bahramifar
authors.forename: Shahin
authors.initials: S
authors.lastname: Ghafari
authors.forename: Ali Akbar
authors.initials: AA
authors.lastname: Zinatizadeh
authors.forename: Sumathi
authors.initials: S
authors.lastname: Sethupathi
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000534:Alum Compounds / Q000737:chemistry; D000536:Aluminum Hydroxide / Q000737:chemistry; D057919:Biological Oxygen Demand Analysis; D005427:Flocculation; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D008962:Models, Theoretical; D009391:Nephelometry and Turbidimetry; D010209:Paper; D059027:Recycling; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000032:analysis / Q000737:chemistry; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D000534:Alum Compounds; D000536:Aluminum Hydroxide; D007220:Industrial Waste; D062065:Wastewater; D000099166:Polyacrylamides; C016213:aluminum oxychloride; C041524:aluminum sulfate